Biometric sensor device with in-glass fingerprint sensor

ABSTRACT

A device includes a touch-mode biometric sensor having a first side facing toward a user and a second side opposite to the first side, and a display arranged under the touch-mode biometric sensor and adjacent to the second side and configured to display an image in response to a sensing result, associated with a biometric feature of the user, of the touch-mode biometric sensor.

TECHNICAL FIELD

The present disclosure is generally related to a biometric sensor deviceand, more particularly, to a sensor device with an in-glass biometricfingerprint sensor.

BACKGROUND

Nowadays the convenience of mobile appliances like IC cards, smartphones and notebook computers brings us better life but also intoprivacy threat. The more widespread these mobile appliances are, themore significant the issue on personal security is. As a result, thedemand for user authentication is becoming more and more important. Somebiometric features, such as fingerprint, palm print, finger vein, irisand voiceprint, have been popularly applied in user authentication.Because of the property of low-cost, easy integration and highreliability, fingerprint sensors have been extensively developed.However, the integration of the existing fingerprint sensor with otherdevice, such as a display module, still may not provide satisfactoryperformance. It may therefore be desirable to have a fingerprint sensordesign that is able to be compatible with the display module whilemaintaining a compact size.

SUMMARY

Embodiments of the present invention provide a device. The deviceincludes a touch-mode biometric sensor having a first side facing towarda user and a second side opposite to the first side, and a displayarranged under the touch-mode biometric sensor and adjacent to thesecond side and configured to display an image in response to a sensingresult, associated with a biometric feature of the user, of thetouch-mode biometric sensor.

In some embodiments, the touch-mode biometric sensor is a fingerprintsensor.

In some embodiments, the touch-mode biometric sensor includes asubstrate made of silicon oxide.

In some embodiments, the substrate is transparent to light emitted bythe display.

In some embodiments, the device further includes a protective layer in amesh pattern around the first side.

In some embodiments, the protective layer is electrically conductive.

In some embodiments, the touch-mode biometric sensor fully overlaps thedisplay.

In some embodiments, the device further includes a cover plate arrangedover the touch-mode biometric sensor and configured to contact astimulus source during a touch event.

In some embodiments, the device further includes a circuit boardlaterally surrounding and electrically connected to the touch-modebiometric sensor.

In some embodiments, the device further includes a frame disposed on thecircuit board and configured to conduct an electric current associatedwith the touch event to one or more fingers and/or a palm of the user.

Embodiments of the present invention discloses a device. The deviceincludes a biometric sensor and a self-light emitting device disposedunder the biometric sensor. The self-light emitting device is configuredto be operated in associated with a biometric feature of a user, whereinlight is generated by the light-emitting device toward the user throughthe biometric sensor.

In some embodiments, the biometric sensor is a touch-mode biometricsensor.

In some embodiments, the self-light emitting device is a pulse oximeter.

In some embodiments, the biometric sensor and the self-light emittingdevice are stacking along a first direction, wherein the device furthercomprises a conductive pillar extending along the first direction andelectrically connected to the biometric sensor.

In some embodiments, the device further includes a first circuit boardlaterally surrounding and electrically connected to the biometricsensor, and a second circuit board is disposed under the self-lightemitting device and electrically connected to the biometric sensorthrough the first circuit board, wherein the first circuit board and thesecond circuit board are secured by the conductive pillar.

In some embodiments, the second circuit board comprises an electronicdevice configured to transmit an electric signal to the user through theconductive pillar.

In some embodiments, the first circuit board comprises a conductivelayer exposed to the user, wherein the electric signal is transmitted tothe user through the conductive layer during a touch event.

In some embodiments, the device further includes a bus electricallycoupling the biometric sensor to the second circuit board.

In some embodiments, the biometric sensor includes a transparentsubstrate and a plurality of sensing electrodes formed in an array onthe transparent substrate.

In some embodiments, the device further includes an optically clearadhesive layer between the biometric sensor and the self-light emittingdevice.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter. It should be appreciated by persons having ordinary skillin the art that the conception and specific embodiments disclosed may bereadily utilized as a basis for modifying or designing other structuresor processes for carrying out the same purposes of the present inventionwithout departing from the spirit and scope of the invention as setforth in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Details of one or more embodiments of the disclosure are set forth inthe accompanying drawings and the description below. Other features andadvantages of the disclosure will be apparent from the description,drawings and claims. Throughout the various views and illustrativeembodiments, like reference numerals are used to designate likeelements. Reference will now be made in detail to exemplary embodimentsillustrated in the accompanying drawings.

FIG. 1A is a cross-sectional view of a biometric sensor device, inaccordance with some embodiments of the present invention.

FIG. 1B is a cross-sectional view of a biometric sensor device, inaccordance with some embodiments of the present invention.

FIGS. 2A and 2B are top views of a protective layer of the biometricsensor device shown in FIG. 1A, in accordance with various embodimentsof the present invention.

FIGS. 3A and 3B are a schematic top view and a schematic bottom view,respectively, of a biometric sensor device, in accordance with variousembodiments of the present invention.

FIGS. 3C and 3D are a schematic left side view and a schematic rightside view, respectively, of a biometric sensor device shown in FIG. 3A,in accordance with various embodiments of the present invention.

FIG. 4 is a cross-sectional view of a biometric sensor device, inaccordance with an embodiment of the present invention.

DETAIL DESCRIPTION

In order to make the disclosure comprehensible, detailed steps andstructures are provided in the following description. Obviously,implementation of the disclosure does not limit special details known bypersons skilled in the art. In addition, known structures and steps arenot described in detail, so as not to limit the disclosureunnecessarily. Preferred embodiments of the disclosure will be describedbelow in detail. However, in addition to the detailed description, thedisclosure may also be widely implemented in other embodiments. Thescope of the disclosure is not limited to the detailed description, andis defined by the claims.

Further, it will be understood that when an element is referred to asbeing “connected to” or “coupled to” or “coupled with” another element,it may be directly connected to or coupled to the other element, orintervening elements may be present.

FIG. 1A is a cross-sectional view of a biometric sensor device 100, inaccordance with some embodiments of the present invention. In someembodiments, the biometric sensor device 100 is configured to sensebiometric data and authenticate the user through the biometric data. Thebiometric sensor device 100 may be adapted to work with an electronicdevice (not shown), such as a smart phone, a personal computer and apersonal digital assistant. Alternatively, the biometric sensor device100 is adapted to work with a personal item protected by a tangible keyor a password, such as a door lock, a combination lock, an identitycard, a safe or the like, such that the biometric sensor device 100 canbe used to protect personal information of the user in place of the keyor password. In the present embodiment, the biometric sensor device 100includes a fingerprint or palm print sensor and the biometric feature isthe user's fingerprint and/or palm print patterns. The biometric sensordevice 100 may be configured as a touch-mode sensor device, in which astimulus source, e.g., the fingerprint, may be received by the sensingelements during a touch event of the biometric sensor device 100.

Referring to FIG. 1A, the biometric sensor device 100 includes a firstcircuit board 110, a second circuit board 120, a third circuit board130, a conductive pillar 140 and a frame 150. The biometric sensordevice 100 further includes a biometric sensor 112, a protective layer114, a cover plate 116, a display 122, and an adhesive layer 124.

In the present embodiment, the display 122 is a self-light emittingdisplay. The display 122 is arranged over and electrically connected tothe second circuit board 120. The display 122 may be formed of anorganic light emitting diode (OLED) panel or other suitableself-luminous display. As an exemplary OLED display panel, the display122 may include, but not limited to, a substrate, an anode layer, a holetransport layer, a light emitting layer, an electron transport layer,and a cathode layer arranged in a stack for emitting light in responseto biasing voltages on the anode layer and the cathode layer. The lightof the display 122 may transmit toward the user above the cover plate116 through the adhesive layer 124, the biometric sensor 112, theprotective layer 114 and the cover plate 116.

The biometric sensor 112 is formed over the display 122. The biometricsensor 112 may include a fingerprint sensor configured to capture orsense fingerprint or palm print data of a user's hand. In someembodiments, the biometric sensor 112 includes a first side 112A facingtoward a finger or a palm of the user and a second side 112B opposite tothe first side 112A. The biometric sensor 112 includes a substrate madeof a transparent material to the light emitted by the display 122 suchthat the image of the display 122 is visible through the biometricsensor 112. The substrate of the biometric sensor 112 is formed ofsilicon oxide and may be in the form of glass or quartz, and thus thebiometric sensor 112 is referred to herein as “in-glass fingerprintsensor.”

The biometric sensor 112 includes one or more sensing electrodes 113 onthe top surface of the substrate of the biometric sensor 112. Thesensing electrodes 113 may include a plurality of sensing electrodes. Insome embodiments, the sensing electrodes 113 include transparentconductive materials, such as indium tungsten oxide (ITO), fluorinedoped tin oxide (FTO) or doped zinc oxide. In some embodiments, thebiometric sensor 112 further include a sensing circuitry (not shown)connected to the sensing electrodes 113. The sensing circuitry mayinclude one or more transistors configured to provide a sensing voltageaccording to the sensing capacitance or sensing voltage according to thesensing electrodes. In some embodiments, the sensing voltage istransmitted to the third circuit board 130 for further processing.

In some embodiments, the adhesive layer 124 is used to adhere thebiometric sensor 112 to the display 122. The adhesive layer 124 mayinclude an optically clear adhesive (OCA), such as LOCA (liquidoptically clear adhesive).

The cover plate 116 is arranged over the biometric sensor 112. In someembodiments, the cover plate 116 is transparent to a radiation spectrumof the display 122 such that the image of the display 122 is visible tothe user through the cover plate 116. The cover plate 116 is made ofglass or other suitable transparent materials.

In some embodiments, the protective layer 114 is formed between thebiometric sensor 112 and the cover plate 116 and configured to protectthe biometric sensor 112 or other features of the biometric sensordevice 100 from damage by an electrostatic discharge (ESD) effect. Insome embodiments, the protective layer 114 is arranged over the firstside 112A of the biometric sensor 112. FIG. 2A shows a top view of theprotective layer 114 overlaid with the biometric sensor 112, in whichthe cross-sectional view of FIG. 1A is taken from the sectional line AAof FIG. 2A. Referring to FIG. 1A and FIG. 2A, the biometric sensor 112includes a plurality of sensing electrodes 113 configured to detect acoupled capacitance with the user's finger. In some embodiments, thesensing electrodes 113 are arranged in a grid or array. In someembodiments, the sensing electrodes 113 are classified into driveelectrodes for providing driving signals and receive electrodes forreceiving sensing signals. The drive electrodes may be alternativelyarranged with the receive electrodes.

In some embodiments, the protective layer 114 includes a conductivelayer 114C and an insulating layer 114D surrounding the conductive layer114C. In some embodiments, the conductive layer 114C is formed ofconductive materials, such as copper, tungsten, aluminum, or othersuitable conductive materials. The insulating layer 114D is used forelectrically insulate the conductive layer 114C from other conductivefeatures of the biometric sensor device 100. The insulating layer 114Dmay be formed of a dielectric material, such as silicon oxide, siliconnitride, resin, epoxy, polymer, or other suitable materials.

The conductive layer 114C is formed over the array of the sensingelectrodes 113 and configured to protect the sensing electrodes 113 fromthe ESD damage. In the present embodiment, the mesh pattern of theconductive layer 114C partitions the electrodes of the sensingelectrodes 113 into electrode groups each including four electrodes froma top-view perspective. However, the present disclosure is not limitedthereto. The mesh pattern of the conductive layer 114C may be configuredotherwise to partition the sensing electrodes 113 into electrode groupsof various electrode numbers. In some embodiments, the protective layer114 has a thickness in the z-direction in a range between about 1 μm andabout 3 μm, such as 2 μm. In some embodiments, the first circuit board110 has a thickness substantially equal to a thickness sum of thebiometric sensor 112, the protective layer 114 and the cover plate 116.In some embodiments, the first circuit board 110 has a thicknesssubstantially equal to a thickness sum of the biometric sensor 112, theprotective layer 114, the cover plate 116 and the adhesive layer 124.

FIG. 2B is a top view of the protective layer 114 overlaid with thebiometric sensor 112, in accordance with another embodiment. In theembodiment shown in FIG. 2B, the protective layer 114 includes aconductive layer 114E and an insulating layer 114D. The conductive layer114E is similar to the conductive layer 114C in many aspects, exceptthat the conductive layer 114E forms a mesh pattern which partitions thearray of sensing electrodes 113 into individual electrodes. In someembodiments, each of the sensing electrodes 113 is laterally surroundedby the mesh pattern of the conductive layer 114E from a top-viewperspective.

Referring to FIG. 1A, the first circuit board 110, the second circuitboard 120 and the third circuit board 130 are arranged in parallel alongthe xy-plane over one another. A stack formed of the cover plate 116,the protective layer 114, the biometric sensor 112, the adhesive layer124 and the display 122 is formed over the second circuit board 120 andextends through the first circuit board 110. The first circuit board110, the second circuit board 120 and the third circuit board 130 areconnected by the conductive pillar 140. The conductive pillar 140 may beformed of a screw, a bolt, a nail, or other conductive members, and mayrun in the z-direction perpendicular to the xy-plane through the firstcircuit board 110, the second circuit board 120 and the third circuitboard 130. In some embodiments, the circuit board 110, 120 or 130 has athickness in the z-direction in a range between about 600 μm and about1000 μm, such as 700 μm. In some embodiments, each of the circuit boards110, 120 and 130 include insulating materials, e.g., a solder mask,configured to electrically insulate the conductive pillar 140 from theconductive features of the circuit boards 110, 120 and 130. Theconductive pillar 140 may serve the function of securing the circuitboards 110, 120 and 130. Further, the conductive pillar 140 isconfigured to provide electric signals, e.g., a sensing clock signal,between the circuit boards 110 and 130. The electric signals may betransmitted to the user's finger and aid in establishing an electricfield between the user's finger and the sensing electrodes 113 tothereby generate a coupled capacitance in the presence of the user'sfinger.

The frame 150 is arranged over the first circuit board 110 and adjacentto the cover plate 116. In some embodiments, the frame 150 include acover portion exposing the cover plate 116. The frame 150 may be formedof a rigid material for providing mechanical support of the firstcircuit board 110. A molding material 118 is provided between the coverplate 116 and the frame 150 to encapsulate the cover plate 116. Themolding material 118 may be formed of resin, epoxy, and the like. Insome embodiments, the frame 150 is formed of conductive materials andconfigured to receive electric signals, in response to a touch event, tothe circuit boards 110, 120 or 130. Although not separately shown, theframe 150 may include a bevel portion surrounding sidewalls of the coverplate 116, the protective layer 114 and the biometric sensor 112.

In some embodiments, the frame 150 includes a conductive material, e.g.,formed of a metallic material, and electrically coupled to theconductive pillar 140. The frame 150 faces the user's finger andconducts electric current through the conductive pillar 140. Duringoperation, when the user's finger touches the cover plate 116, theuser's finger will also touches the conductive frame 150. In this way,the finger will conduct current by help of the frame 150 to facilitatethe sensing process of the fingerprint. In some embodiments, the firstcircuit board 110 includes a conductive layer exposed from the uppersurface of the first circuit board 110. The conductive layer of thefirst circuit board 110 may face the frame 150 and the finger of theuser, in which the conductive layer is configured to convey electricsignals to the user's finger from the conductive pillar 140 during atouch event. In some other embodiments, the frame 150 is formed ofnon-conductive materials, such as glass, plastics, ceramic, or the like.

The first circuit board 110 is configured to support the frame 150. Insome embodiments, the first circuit board 110 is configured to secureand electrically connect to the biometric sensor 112. The first circuitboard 110 may be a printed circuit board (PCB), a metal core PCB (MCPCB)or a flexible PCB (FPCB). The first circuit board 110 may include anopening defined by a peripheral region, in which the biometric sensor112 is embedded in the opening and laterally surrounded by theperipheral region of the first circuit board 110. In some embodiments,although not explicitly shown, the first circuit board 110 includes abus, e.g., formed of conductive wirings or vias, electrically connectedto the biometric sensor 112.

In some embodiments, the first circuit board 110 includes a conductivelayer 117 formed on the upper surface of the first circuit board 110 andlaterally surrounding the cover plate 116. The conductive layer 117 maybe electrically coupled to the frame 150 and configured to transmitelectric signals, in response to a touch event, to the second circuitboard 120 or the third circuit board 130 through the frame 150.

The second circuit board 120 includes an upper surface on which thedisplay 122 is disposed. In some embodiments, the second circuit board120 is configured to electrically connect the display 122 with externaldevices. The second circuit board 120 may be a PCB, a MCPCB or a FPCB.In some embodiments, the second circuit board 120 includes an electronicdevice 126 disposed on a lower surface thereof opposite to the uppersurface of the second circuit board 120. The electronic device 126 maybe a display driver device configured to control display functions ofthe display 122. In some embodiments, the second circuit board 120includes a bus 128 to electrically connect the display 122 with theelectronic device 126. The bus 128 may a bus formed as a flexibleprinted circuit (FPC), or including bonding wires or conductive viasextending through the second circuit board 120.

The third circuit board 130 is configured to electrically connect thefirst circuit board 110 and the second circuit board 120 to externaldevices. The third circuit board 130 may be a PCB, a MCPCB or a FPCB.The third circuit board 130 includes an electronic device 132, aconnector 134 and a connection port 136 disposed on a lower surface. Thethird circuit board 130 also includes and an electronic device 138 and aconnector 142 disposed on an upper surface opposite to the lower surfaceof the third circuit board 130.

The electronic device 132 may be a processor, a microcontroller, asignal processing unit, or the like configured to control the sensingfunctions of the biometric sensor 112 and the display functions of thedisplay 122. The third circuit board 130 is electrically connected tothe biometric sensor 112 through a bus 135, e.g., an FPC, a bondingwire, or the connector 134 on the third circuit board 130. The connector134 may be a socket or solder pads to be electrically coupled to the bus135. The connector 134 may be a serial connector or a parallelconnector. In some embodiments, the connection port 136 is a universalserial bus (USB) port for electrically connect the third circuit board130 with devices external to the biometric sensor device 100.

In some embodiments, the electronic device 138 is a sensor driver deviceconfigured to enable the sensing functions of the biometric sensor 112.In some embodiments, the electronic device 132 is configured to controlthe biometric sensor 112 and the display 122 through the electronicdevices 138 and 126, respectively. The electronic device 138 may beelectrically connected to the biometric sensor 112 through the bus 135and the connector 134, and optionally through conductive vias of thethird circuit board 130. In some embodiments, the electronic device 138is configured to generate the sensing clock signals and transmit thesensing clock signals to the user's finger through the first circuitboard 110 or the frame 150.

The connector 142 may electrically connect the third circuit board 130to the second circuit board 120. In some embodiments, the connector 142includes a bus, e.g., an FPC or a bonding wire, and a socket forelectrically coupling the second circuit board 120 to the third circuitboard 130 to thereby provide power or signals between the circuit boards120 and 130. The connector 142 may be a serial connector or a parallelconnector.

During a touch event, the biometric sensor 112 is configured to sensethe presence of the user's finger. The biometric sensor 112 and theelectronic device 132 are configured to authenticate the user throughrecognizing the fingerprint pattern of the user. In some embodiments,the display 122 is configured to generate an image which containsinstructions or recognition results that can be shown to the userthrough the in-glass biometric sensor 112. In some embodiments, thedisplay 122 is configured to show the image to the user in response to asensing result, associated with a biometric feature of the user, of thebiometric sensor 112. In some embodiments, the display 122 is configuredto display the image associated with the sensing result provided by thebiometric sensor 112 before, during, or after the fingerprintrecognition process is performed. Since the substrate and the sensingelectrodes 113 of the biometric sensor 112 are made of transparentmaterials, the image of the display 122 can be readily visible to theuser during the touch event. No extra areas are required for theindividual biometric sensor 112 and the display 122. Therefore, thebiometric sensor device 100 is capable of providing both the display andfingerprint recognition functions with a minimized device size.

FIG. 1B is across-sectional view of a biometric sensor device 200, inaccordance with some embodiments of the present invention. In someembodiments, the biometric sensor device 200 is similar to the biometricsensor device 100 in many aspects, and thus descriptions of thesesimilar features are not repeated for brevity. The biometric sensordevice 200 is different from the biometric sensor device 100 in that theconductive layer 114C, which laterally surrounds the sensing electrodes113, is arranged in the same level of the sensing electrodes 113. Insuch arrangement, the conductive layer 114C is arranged on the firstside 112A of the biometric sensor 112. In some embodiments, the sensingelectrodes 113 are insulated from the conductive layer 114C by aninsulating material. The insulating material may include a materialsimilar to the tha of the insulating layer 114D. The insulating layer isarranged over the sensing electrodes 113 and the conductive layer 114C.

FIGS. 3A and 3B are a schematic top view and a schematic bottom view,respectively, of a biometric sensor device 300, in accordance withvarious embodiments of the present invention. FIGS. 3C and 3D are aschematic left side view and a schematic right side view, respectively,of the biometric sensor device 300 shown in FIG. 3A, in accordance withvarious embodiments of the present invention. The biometric sensordevice 300 is similar to the biometric sensor device 100 in manyfeatures, and thus descriptions of these features are omitted forbrevity. Referring to FIG. 3A, the top view of the biometric sensordevice 300 includes the cover plate 116, the biometric sensor 112 andthe display 122 stacked in the z-direction, in which the screen of thedisplay 122 is visible through the biometric sensor 112 and the coverplate 116. The biometric sensor 112 includes a sensing circuit 304 andthe sensing electrodes 113. In some embodiments, the sensing circuit 304may be non-transparent to the light emitted by the display 122. In someembodiments, the sensing circuit 304 is formed of semiconductormaterials, such as silicon, germanium, or the like. In some embodiments,the biometric sensor 112 fully overlaps the display 122 from a top-viewperspective. In some embodiments, the sensing electrodes 113 of thebiometric sensor 112 occupy an area substantially equal to the area ofthe display 122. In some embodiments, the biometric sensor 112 has anarea greater than the area of the display 122 due to the sensing circuit304.

In some embodiments, referring to FIGS. 3A, 3C and 3D, the first circuitboard 110 laterally surrounds the cover plate 116 and the biometricsensor 112. In some embodiments, the first circuit board 110 includesthe conductive layer 117 formed on the upper surface of the firstcircuit board 110 and laterally surrounding the cover plate 116. Theconductive layer 117 may be in a circular shape or a ring shape, and issubstantially level with the cover plate 116 or arranged facing thefinger of the user. In some embodiments, the bus 135 is electricallycoupled to the first circuit board 110 or the sensing circuit 304 of thebiometric sensor 112.

FIG. 4 is a cross-sectional view of a biometric sensor device 400, inaccordance with an embodiment of the present invention. The biometricsensor device 400 is similar to the biometric sensor device 100 in manyfeatures, and thus descriptions of these features are omitted forbrevity. The biometric sensor device 400 differs from the biometricsensor device 100 in that the biometric sensor device 400 alternativelyor additionally includes a pulse oximeter, or simply oximeter, 402serving as a self-light emitting device and arranged on the secondcircuit board 120. In some embodiments, the pulse oximeter 402 isconfigured to measure the oxygen level in the user's blood in anon-invasive manner through transmission of sensing light to the user'sfinger through the biometric sensor 112 and the cover plate 116. In someembodiments, the sensing light of the pulse oximeter 402 is in a rangeof red light and infrared light. In a touch event, the biometric sensordevice 400 is capable of performing user authentication and blood oxygenlevel at the same time. In addition, due to the transparent substrateand the transparent sensing electrode 113 of the biometric sensor 112,the sensing light of the pulse oximeter 402 can be readily transmittedto the user and reflected to the pulse oximeter 402 during the touchevent. No extra areas are required for the individual biometric sensor112 and the pulse oximeter 402. Therefore, the biometric sensor device400 is capable of providing both the blood oxygen level measurement andfingerprint recognition functions with a minimized device size.

Although the disclosure has been shown and described with respect to oneor more implementations, equivalent alterations and modifications willoccur to others skilled in the art based upon a reading andunderstanding of this specification and the annexed drawings. Thedisclosure includes all such modifications and alterations and islimited only by the scope of the following claims.

What is claimed is:
 1. A device, comprising: a touch-mode biometricsensor having a first side facing toward a user and a second sideopposite to the first side; and a display arranged under the touch-modebiometric sensor and adjacent to the second side and configured todisplay an image in response to a sensing result, associated with abiometric feature of the user, of the touch-mode biometric sensor. 2.The device of claim 1, wherein the touch-mode biometric sensor is afingerprint sensor.
 3. The device of claim 1, wherein the touch-modebiometric sensor includes a substrate made of silicon oxide.
 4. Thedevice of claim 3, wherein the substrate is transparent to light emittedby the display.
 5. The device of claim 1, further comprising aprotective layer in a mesh pattern around the first side.
 6. The deviceof claim 5, wherein the protective layer is electrically conductive. 7.The device of claim 1, wherein the touch-mode biometric sensor fullyoverlaps the display.
 8. The device of claim 1, further comprising acover plate arranged over the touch-mode biometric sensor and configuredto contact a stimulus source during a touch event.
 9. The device ofclaim 8, further comprising a circuit board laterally surrounding andelectrically connected to the touch-mode biometric sensor.
 10. Thedevice of claim 9, further comprising a frame disposed on the circuitboard and configured to conduct an electric current associated with thetouch event to a finger of the user.
 11. A device, comprising: abiometric sensor; and a self-light emitting device disposed under thebiometric sensor and configured to be operated in associated with abiometric feature of a user, wherein light is generated by theself-light emitting device toward the user through the biometric sensor.12. The device of claim 11, wherein the biometric sensor is a touch-modebiometric sensor.
 13. The device of claim 11, wherein the self-lightemitting device is a pulse oximeter.
 14. The device of claim 11, whereinthe biometric sensor and the self-light emitting device are stackingalong a first direction, wherein the device further comprises aconductive pillar extending along the first direction and electricallyconnected to the biometric sensor.
 15. The device of claim 14, furthercomprising: a first circuit board laterally surrounding and electricallyconnected to the biometric sensor; and a second circuit board isdisposed under the self-light emitting device and electrically connectedto the biometric sensor through the first circuit board, wherein thefirst circuit board and the second circuit board are secured by theconductive pillar.
 16. The device of claim 15, wherein the secondcircuit board comprises an electronic device configured to transmit anelectric signal to the user through the conductive pillar.
 17. Thedevice of claim 16, wherein the first circuit board comprises aconductive layer exposed to the user, wherein the electric signal istransmitted to the user through the conductive layer during a touchevent.
 18. The device of claim 15, further comprising a bus electricallycoupling the biometric sensor to the second circuit board.
 19. Thedevice of claim 11, wherein the biometric sensor comprises a transparentsubstrate and a plurality of sensing electrodes formed in an array onthe transparent substrate.
 20. The device of claim 11, furthercomprising an optically clear adhesive layer between the biometricsensor and the self-light emitting device.